Reputation: 11
I have a strange problem:
Database: Firebird Connection String: Driver={Firebird/InterBase(r)driver};Dbname=xxx;CHARSET=NONE;UID=xxx; PASSWORD=xxx
I use a set of ODBC classes to operation(select) the database table
when I loop the db records with OdbcDataReader.GetValue(), if some fields(char type) have no value(char_length()=0), it would get the last record field value; if fields has the value, it's ok(does not get the value from last record)
My code likes below:
var dr = this.SqlExecutor.Open(sql); //sql is String variable that stored the sql statement
while (dr.Read())
{
this.Logger.Info("-----Customer_Id: " + this.SqlReader.GetFieldAsString(dr, "Customer_Id") + " -----"); // this not duplicated because it's not empty
this.Logger.Info("-----Customer_Email: " + this.SqlReader.GetFieldAsString(dr, "Customer_email") + " -----"); //this would if some records has empty value
}
// the method SqlExecutor.Open(sql) and SqlReader.GetFieldAsString() please refer to below:
public IDataReader Open(string sql)
{
this.Logger.Debug("sql: " + sql);
if (this.reader != null && !this.reader.IsClosed)
{
this.reader.Close();
this.reader = null;
}
try
{
this.cmdForSelect.Connection = this.conn;
this.cmdForSelect.CommandTimeout = 120;
this.cmdForSelect.CommandText = sql;
this.cmdForSelect.Parameters.Clear();
foreach (var p in this.dbParameters)
{
this.cmdForSelect.Parameters.Add(p);
}
this.reader = cmdForSelect.ExecuteReader();
}
catch (Exception ex)
{
this.Logger.Error("There is an error: {0}", ex.Message);
this.Logger.Info("Error sql query:" + sql);
throw;
}
finally
{
this.ClearParameters();
}
return this.reader;
}
public string GetFieldAsString(IDataReader dr, string fieldName)
{
try
{
var value = dr.GetValue(dr.GetOrdinal(fieldName));
if (value == DBNull.Value)
{
return string.Empty;
}
return Convert.ToString(value);
}
catch
{
return string.Empty;
}
}
Besides, this case is fine on my computer, just happened on my customer's computer, I feel this does not matter with mycode, anyone know this, please help me, thanks a lot!!!
Upvotes: 0
Views: 60
Reputation: 1
Assuming the actual code is not posted in your question; I think the problem is with re-initiation of the variable in the actual code. You need to revisit the code and check the IF-ELSE condition you have applied on the this.SqlReader.GetFieldAsString(dr, "Customer_email")
Upvotes: 0